Gears

An ordinary manual transmission car has 3 pedals: gas, brake, and clutch. How about the DCT? Does the DCT only have gas and brake? Does it have paddle shifters? Please answer all questions and how do you drive it? Is the procedure just like the SMG in the BMW M5 and M6?

From a driving perspective yes it’s the same as the M5 and M6 with SMG as there is no clutch pedal. The biggest difference is the uninterupted flow of power.
The M DCT with Drivelogic combines two gearbox
components in one common housing with the same compact dimensions as a conventional manual gearbox. The “heart” of the new M double-clutch transmission in technical terms is formed by the two oil-cooled wet clutches.
One of the two clutches is for the even (2, 4, 6), the other for the uneven (1, 3, 5, 7) gears and, in addition, for the reverse gear. While driving, one of the two clutches is always closed, the other is open.
When accelerating – and when shifting down – the clutches are activated in an alternating process, one after the other. When shifting gears, the first clutch opens just as the second clutch is closing. This ensures an absolutely smooth and comfortable and at the same time an incomparably
fast gearshift without the slightest interruption in the flow of power.
This interaction of two clutches ensures a super fast rate of gear change in particular because the transmission control unit pre-selects the next gear with the transmission ratio matched ideally to engine and road speed and keeps this
gear waiting for immediate operation.
So when you’re accelerating, say, in third gear, an immediate flow of power is ensured by the appropriate clutch and the gearbox component controlling the uneven gears.
While all this is happening, the gearbox segment responsible for the even gears shifts to the gear required, in this case to fourth gear. The only operation required for this purpose is to close the clutch for fourth gear, at the same time opening the clutch for third gear, the power of the engine then being transmitted through the new gear with its different ratio to the wheels.
This entire process takes only a few milliseconds, meaning that in the time a skilled driver takes to press down the clutch pedal the DCT has easily completed the entire process of shifting gears, continuing to accelerate in the next gear higher up.
There are also 11 programs of driving styles ranging from auto comfort to super sport.

Oh – and of course launch control! Houston – we have lift off….

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when i put my car in reverse nothing happens . All the forward gears work fine. the car has 200,000 on it. If I have to change the tranny ,well the car is through. too bad cause its black on black all tinted , but tranny replacement is 3500 . Could it be throttle body fluids changed

One thing you can check out is this.
When you put it in reverse does the "R" pop up on your dash? If it does not you have a bad shift selector unit. This unit is inside the car wrapped around the shifter. If that part is faulty for the (R) position. Also unplug the shift program switch and try reverse. It to can cause problems. Don’t worry the trans will not blowup if you unplug it and try shifting.

That is one common fault. BUT the 740 trans is a weak transmission. They go out often and its a nasty job changing them. The exhaust alone is like 400 lbs..

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I own a 1993 740 I IT has 200.000 mile on her but she runs great. This past year have put over 3000 in repairs. sencers,vacume, and intake problems to get her to pass smog. Finally I got all that done . The other day when I put her in reverse I got nothing. Whats strange is all the forward gears shift smoothly like new. Is this something that is electronic, ?I know that trannys for these cars cost allot so if I need a new one well the car will be totaled. It would cost more than shes worth. I am hoping that someone out there who is a bmw expert can tell me something simple that I can do or check to solve my problem. Even if I can get the reverse to barely work I would be happy with that. I only useit to back out of my garage to leave Any ideas at all I would be willing to try the car still looks great It all Black on black leather tinted windows help!!
oh by the way its a automatic

Hi there you don’t say if its auto or manual?
If manual, I suggest you check out the selector lever, and work out just what it is doing that isn’t happening with forward gears.
Hope this helps a bit.

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it seems fairly hard to go past the gate and get into reverse all the other gears seem fine to go into what is the problem?

Is it the gear that’s difficult to get in, or just that you have a tough time getting it past the spring-loaded detent that stops you selecting reverse by mistake?

If it’s the latter, change your technique a little. Actually wind up (only a little!) and slap the lever over to the left, through the detent. It’s easier than trying to push it sideways.

While it’s possibly it’s your clutch on the way out, I’d suggest changing your transmission fluid first. It may help, and it’s much cheaper! Use a quality synthetic: BMW’s own fluid, Redline D4ATF, Mobil 1 ATF or Royal Purple Syncromax. When you do this, be sure to loosen the fill plug before the drain plug! You don’t want to drain the fluid only to find you can’t get it back in.

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